A typical electrical connector combination includes a plug connector and a receptacle connector, both of which mount or house interengageable electrical terminals. The plug connector is inserted into or mated with the receptacle connector to interengage the terminals. The terminals may take a variety of configurations, including male and female or pin and socket terminals.
Known female terminals comprise a generally tubular-shaped contact section for engaging a complementary male terminal, and a connection section on the opposing end for connection to a conducting wire. The contact section typically employs flexible elements for applying retentive normal forces to an engaged complementary male terminal. For example, U.S. Pat. No. 6,095,874 discloses an electrical receptacle terminal comprising a contact section having a pair of opposed cantilever beam contact arms. Free ends of the contact arms are resiliently biased toward one another such that their original position defines a space that is of a smaller diameter than a complementary male terminal. The free ends flex outwardly upon insertion of a male terminal, thereby applying normal forces to the male terminal sufficient to maintain the inter-engagement and electrical connectivity.
Many known female terminals employ only a single flexible element in the form of an arcuate-shaped spring housed within the contact section. The spring urges a complementary male terminal into engagement with one of the sidewalls forming the contact section. Ooya et al., in U.S. Pat. No. 6,139,376, disclose such a female terminal, and will now be described with reference to FIGS. 1 and 2. Female electrical terminal 9 includes a contact section 12 and a connection section 14. Contact section 12 is generally box-shaped or rectangular in cross-section and mounts a spring contact element 13 for resiliently gripping a male terminal. As can be seen in the figures, spring contact element 13 has an exposed leading edge 15. Having access to the spring contact element's leading edge, however, is problematic, as it can lead to product damage and/or failure. For example, if a complementary male terminal is misaligned upon engagement with the female terminal, the male terminal can hit the contact element leading edge and damage it. Minimally, the damage results in a non-reliable electrical connection between the inter-engaged terminals. In a worse case scenario, the spring contact element is damaged and distorted to the extent that it becomes separated from the remaining portions of the female terminal. Without the spring contact element, the female terminal will fail.
Quality control related to the manufacture of male and female electrical terminals, as well as related to methods of interengaging the same, may decrease the potential for misaligned engagement; however, the potential for tampering with the contact element, through the use of a small or sharp instrument, still exists when the spring contact element's leading edge is exposed. There have been efforts to reduce the potential for damage to the spring contact element by impeding access to its leading edge, as can be seen from prior art FIG. 3, taken from U.S. Pat. No. 5,271,741. However, the contact element leading edge 18 is still exposed to potential failure-inducing damage.
In summary, the prior art has not been able to come up with functional and robust terminal designs. Accordingly, a need still exists fora female electrical terminal that protects incorporated contact elements from damage.